Re: [PATCH 0/2] NET: Accurate packet scheduling for ATM/ADSL
From: Andy Furniss <hidden>
Date: 2006-06-14 15:31:54
jamal wrote:
I have taken linux-kernel off the list. Russell's site is inaccessible to me (I actually think this is related to some DNS issues i may be having) and your masters is too long to spend 2 minutes and glean it; so heres a question or two for you: - Have you tried to do a long-lived session such as a large FTP and seen how far off the deviation was? That would provide some interesting data point. - To be a devil's advocate (and not claim there is no issue), where do you draw the line with "overhead"?
Me and many others have run a smilar hack for years, there is also a userspace project still alive which does the same. The difference is that without it I would need to sacrifice almost half my 288kbit atm/dsl showtime bandwidth to be sure of control. With the modification I can run at 286kbit / 288 and know I will never have jitter worse than the bitrate latency of a mtu packet. The 286 figure was choses to allow a full buffer to drain/ allow for timer innaccuracy etc. On a p200 with tsc, 2.6.12 it's never gone over for me - though talking of timers I notice on my desktop 2.6.16 I gain 2 minutes a day now. Andy.